This patch is worth a lot, speed-wise.

This does introduce a proper stack of IFiles to handle included files:
instead of having the current file be a special case, it's also an IFile.

The corresponding code is slightly unobfuscated, removing the error-prone
ParseEOF function, freeing the filename systematically (thus, main.c needs
to strdup stdin), and merging both include functions lookup into one.

The speed gain comes from changing the IFile structure to merge with
fgetln seamlessly.

The low-level parse code is mostly moved to a new file, lowparse.c, to
make things easier to read (see next patch as well).

Accordingly, util.c gains a fgetln.

Note the interaction between Parse_File, Dir_FindFile, and ReadMakefile in
main.c. This patch closes a subtle memory hole (only the Makefile names,
so rather small).

Reviewed by miod@.

1 files changed, 292 insertions, 0 deletions

diff --git a/usr.bin/make/lowparse.c b/usr.bin/make/lowparse.c
new file mode 100644
index 00000000000..3c1faeee0dc
--- /dev/null
+++ b/usr.bin/make/lowparse.c
@@ -0,0 +1,292 @@
+/*	$OpenBSD: lowparse.c,v 1.1 2000/06/23 16:39:45 espie Exp $ */
+
+/* low-level parsing functions. */
+
+/*
+ * Copyright (c) 1999,2000 Marc Espie.
+ *
+ * Extensive code changes for the OpenBSD project.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OPENBSD
+ * PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <assert.h>
+#include "make.h"
+#include "buf.h"
+#include "lowparse.h"
+
+#ifdef CLEANUP
+static LIST	    fileNames;	/* file names to free at end */
+#endif
+
+static LIST     includes;  	/* stack of IFiles generated by
+				 * #includes */
+
+static IFile *new_ifile __P((char *, FILE *));
+static IFile *new_istring __P((char *, char *, unsigned long));
+static void free_ifile __P((IFile *));
+static void ParseVErrorInternal __P((char *, unsigned long, int, char *, va_list));
+static int skiptoendofline __P((void));
+static int ParseSkipEmptyLines __P((Buffer));
+static int	    fatals = 0;
+
+/*-
+ * ParseVErrorInternal  --
+ *	Error message abort function for parsing. Prints out the context
+ *	of the error (line number and file) as well as the message with
+ *	two optional arguments.
+ *
+ * Side Effects:
+ *	"fatals" is incremented if the level is PARSE_FATAL.
+ */
+/* VARARGS */
+static void
+#ifdef __STDC__
+ParseVErrorInternal(char *cfname, unsigned long clineno, int type, char *fmt,
+    va_list ap)
+#else
+ParseVErrorInternal(va_alist)
+	va_dcl
+#endif
+{
+	(void)fprintf(stderr, "\"%s\", line %lu: ", cfname, clineno);
+	if (type == PARSE_WARNING)
+		(void)fprintf(stderr, "warning: ");
+	(void)vfprintf(stderr, fmt, ap);
+	va_end(ap);
+	(void)fprintf(stderr, "\n");
+	if (type == PARSE_FATAL)
+		fatals ++;
+}
+
+/*-
+ * Parse_Error  --
+ *	External interface to ParseVErrorInternal; uses the default filename
+ *	Line number.
+ */
+/* VARARGS */
+void
+#ifdef __STDC__
+Parse_Error(int type, char *fmt, ...)
+#else
+Parse_Error(va_alist)
+	va_dcl
+#endif
+{
+	va_list ap;
+#ifdef __STDC__
+	va_start(ap, fmt);
+#else
+	int type;		/* Error type (PARSE_WARNING, PARSE_FATAL) */
+	char *fmt;
+
+	va_start(ap);
+	type = va_arg(ap, int);
+	fmt = va_arg(ap, char *);
+#endif
+
+	ParseVErrorInternal(current->fname, current->lineno, type, fmt, ap);
+}
+
+static IFile *
+new_ifile(name, stream)
+    char *name;
+    FILE *stream;
+{
+    IFile *ifile;
+#ifdef CLEANUP
+    Lst_AtEnd(&fileNames, name);
+#endif
+
+    ifile = emalloc(sizeof(*ifile));
+    ifile->fname = name;
+    /* Naturally enough, we start reading at line 0 */
+    ifile->lineno = 0;
+    ifile->F = stream;
+    ifile->ptr = ifile->end = NULL;
+    return ifile;
+}
+
+static void
+free_ifile(ifile)
+    IFile *ifile;
+{
+    if (ifile->F)
+    	(void)fclose(ifile->F);
+    else
+    	free(ifile->str);
+    /* Note we can't free the file names yet, as they are embedded in GN for
+     * error reports. */
+    free(ifile);
+}
+
+static IFile *
+new_istring(str, name, lineno)
+    char *str;
+    char *name;
+    unsigned long lineno;
+{
+    IFile *ifile;
+
+    ifile = emalloc(sizeof(*ifile));
+    ifile->fname = name;
+    ifile->F = NULL;
+    /* Strings are used from for loops... */
+    ifile->lineno = lineno;
+    ifile->ptr = ifile->str = str;
+    ifile->end = str + strlen(str);
+    return ifile;
+}
+
+
+/*-
+ *---------------------------------------------------------------------
+ * Parse_FromString  --
+ *	Start Parsing from the given string
+ *
+ * Side Effects:
+ *	A structure is added to the includes Lst and readProc, lineno,
+ *	fname and curFILE are altered for the new file
+ *---------------------------------------------------------------------
+ */
+void
+Parse_FromString(str, lineno)
+    char 		*str;
+    unsigned long 	lineno;
+{
+    if (DEBUG(FOR))
+	(void)fprintf(stderr, "%s\n----\n", str);
+
+    if (current != NULL)
+	Lst_AtFront(&includes, current);
+    current = new_istring(str, current->fname, lineno);
+}
+
+
+void 
+Parse_FromFile(name, stream)
+    char		*name;
+    FILE		*stream;
+{
+    if (current != NULL)
+    	Lst_AtFront(&includes, current);
+    current = new_ifile(name, stream);
+}
+
+/*-
+ *---------------------------------------------------------------------
+ * Parse_NextFile -- 
+ *	Called when EOF is reached in the current file. If we were reading
+ *	an include file, the includes stack is popped and things set up
+ *	to go back to reading the previous file at the previous location.
+ *
+ * Results:
+ *	CONTINUE if there's more to do. DONE if not.
+ *
+ * Side Effects:
+ *	The old curFILE, is closed. The includes list is shortened.
+ *	lineno, curFILE, and fname are changed if CONTINUE is returned.
+ *---------------------------------------------------------------------
+ */
+Boolean
+Parse_NextFile()
+{
+    IFile *next;
+
+    next = (IFile *)Lst_DeQueue(&includes);
+    if (next != NULL) {
+	if (current != NULL)
+	    free_ifile(current);
+	current = next;
+    	return TRUE;
+    } else
+    	return FALSE;
+}
+
+
+int
+newline()
+{
+    size_t len;
+
+    if (current->F) {
+	current->ptr = fgetln(current->F, &len);
+	if (current->ptr) {
+	    current->end = current->ptr + len;
+	    return *current->ptr++;
+	} else {
+	    current->end = NULL;
+	}
+    }
+    return EOF;
+}
+
+void 
+ParseUnreadc(c)
+	char c;
+{
+	current->ptr--;
+	*current->ptr = c;
+}
+
+unsigned long
+Parse_Getlineno()
+{
+    return current->lineno;
+}
+
+const char *
+Parse_Getfilename()
+{
+    return current->fname;
+}
+
+#ifdef CLEANUP
+void
+LowParse_Init()
+{
+    Lst_Init(&includes);
+    current = NULL;
+}
+
+void
+LowParse_End()
+{
+    Lst_Destroy(&includes, NOFREE);	/* Should be empty now */
+}
+#endif
+	
+
+void
+Finish_Errors()
+{
+    if (current != NULL) {
+    	free_ifile(current);
+	current = NULL;
+    }
+    if (fatals) {
+	fprintf(stderr, "Fatal errors encountered -- cannot continue\n");
+	exit(1);
+    }
+}